10. Susan drives her car at an average speed of s miles per hour for t hours and travels 215 miles. Which of the following equations represents this information?
Answer: A
st=215
The equation st=215 effectively represents the relationship between speed, time, and distance, where s is the average speed in miles per hour, t is the time in hours, and the product of speed and time equals the distance traveled, which is 215 miles.
A) st=215
This option correctly formulates the relationship between speed, time, and distance based on the formula Distance = Speed × Time. Here, st accurately represents the distance of 215 miles traveled by Susan, making it the right choice.
B) 215+t=s
This option is incorrect because it wrongly rearranges the relationship. It suggests that speed (s) equals the distance (215) plus time (t), which does not conform to the basic distance formula.
C) s/t=215
This option is also incorrect as it represents the average speed divided by time, yielding a different value rather than the relationship between distance, speed, and time. The correct formula involves multiplication, not division.
D) s+t=215
This option misinterprets the relationship by suggesting that speed plus time equals distance, which is not mathematically accurate. The sum of speed and time does not equate to distance traveled.
Conclusion
The equation st=215 is the only option that accurately reflects the fundamental relationship of distance traveled through the multiplication of speed and time. All other options fail to represent this relationship correctly, either through incorrect operations or misinterpretations of the variables involved.